Roll formed step rail for a vehicle

ABSTRACT

A roll formed step rail for a vehicle comprises an elongated rail body including a continuous rail wall of substantially uniform thickness. The rail wall describes a continuous cross-sectional profile between two elongated free edges, the cross-sectional profile of the rail being substantially uniform along the length of the rail body. The cross-sectional profile of the rail body includes a relatively flat top portion disposed between a substantially semi-circular front curved portion and a substantially quarter-circular rear curved portion. A rear mounting lip extends forward from the rear curved portion to one of the elongated free edges. A front mounting lip extends upward and then rearwards from the front curved portion to another of the elongated free edges. The elongated free edges are generally in line with one another, but spaced apart to define a longitudinal channel therebetween having a predetermined width. The rail body is formed from a sheet of material by a process of roll forming.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. ProvisionalApplication No. 60/741,522 filed Dec. 1, 2005.

TECHNICAL FIELD OF THE INVENTION

This invention is related to automotive vehicle body/chassis accessoriessuch as running boards, side bars and tube steps, and more particularly,to step rails manufactured using a roll forming process for mounting onthe sides of vehicles such as pickup trucks and sport utility vehicles.

BACKGROUND OF THE INVENTION

It is well known to mount body/chassis accessories such as runningboards, side bars or tube steps (referred to collectively herein as“step rails”) below the side doors of automotive vehicles such as pickuptrucks and sport utility vehicles (SUVs) to provide a convenient stepfor use when entering/exiting the vehicle and for protection of thevehicle against side body damage. In addition, these step railsfrequently serve as styling members intended to personalize or enhancethe appearance of the vehicle. As such, both the mechanical strengthproperties and the external appearance properties of step rails areimportant. Further, since step rails are exposed to the rain, ice, mud,road chemicals (e.g., salt) and other harsh environmental materials, itis desirable that they be resistant to corrosion and/or surface finishdegradation.

Conventional step rails are typically formed by bending tubular metalstock (e.g., where a tubular cross section is desired), by stamping flatmetal blanks (e.g., where irregular, concave and/or convex surfacefeatures are desired), or by metal extrusion (e.g., where a constantcross section is desired). Commonly used materials for bending andstamping include steels, stainless steels and aluminum alloys, whereasextrusion in typically restricted to aluminum alloys. Ordinary steelstep rails are typically painted, chrome plated, or powder coated toprovide corrosion resistance and an attractive appearance. Stainlesssteel and aluminum alloy step rails may be left bare since thosematerials are inherently corrosion resistant, however, they are oftenpolished to produce a reflective (i.e., “mirror”) finish or brushed toproduce a matte (i.e., “brushed”) finish. Less frequently, they may alsobe painted or powder coated.

It will be appreciated that it is typically much easier (an hence, lessexpensive) to produce a high quality, uniform surface finish on basicmetal stock (e.g., straight tubes, flat sheets, etc.) than it is oncomplex shapes such as a formed step rail. This is especially true inthe case of bare metal finishes such as mirror and brushed finishes.Thus, it is desirable that the surface finish be applied to the basicmetal stock before forming. However, the bending, stamping and extrusionprocesses conventionally used in forming step rails tend to mar, distortor otherwise damage the surface finish during forming. For low qualityparts, such damage may be acceptable, given the savings in manufacturingcosts. But for top-quality parts, even minor surface finishimperfections may cause the part to be rejected. Thus, the cost savingsachieved by pre-finishing the stock may be lost due to a high defectrate in the finished product. A need therefore exists for a high qualityformed step rail made from pre-finished stock using a process that willpreserve the original high quality surface of the stock in the finishedproduct.

It will also be appreciated that step rails must be strong enough tosupport the loads imposed upon them (e.g., the weight of passengers onthe step) without failing, and be stiff enough to avoid undue deflection(“flexing”) and/or vibration during use. At the same time, it isdesirable to minimize the overall weight and amount of material used inthe step rail for performance and cost reasons. A need therefore existsfor a formed step rail having a structural configuration that isrelatively efficient, i.e., producing high strength and stiffness forthe amount of material used.

After fabrication, the step rails must be mounted on the vehicle. Thisis typically accomplished through the use of bracket systems designedfor the particular step rail/vehicle combination. However, ordinaryvariation in the location of the mounting holes provided on the vehicleby its manufacturer can sometimes make it difficult to install andadjust the step rails without requiring “field modification” of thebracket system and/or step rail itself. Such modifications areundesirable as they introduce additional complexity (and hence,additional cost) to the step rail mounting. Further, if done improperly,such modifications may also affect the structural integrity of the steprail. A need therefore exists for a bracket system which provides foruncomplicated installation and adjustment of the step rails even in theface of normal variation in vehicles.

While necessary for mounting the step rail to the vehicle, the bracketsystem is typically not considered a styling member. A need thereforeexists for a step rail/bracket system combination which conceals as muchof the bracket system as possible when viewed from normal viewingangles.

SUMMARY OF THE INVENTION

The present invention disclosed and claimed herein comprises, in oneaspect thereof, a roll formed step rail for a vehicle including anelongated rail body having a continuous rail wall of substantiallyuniform thickness. The rail wall describes a continuous cross-sectionalprofile between two elongated free edges, the cross-sectional profile ofthe rail being substantially uniform along the length of the rail body.The cross-sectional profile of the rail body includes a relatively flattop portion disposed between a substantially semi-circular front curvedportion and a substantially quarter-circular rear curved portion. A rearmounting lip extends forward from the rear curved portion to one of theelongated free edges. A front mounting lip extends upward and thenrearwards from the front curved portion to another of the elongated freeedges. The elongated free edges are generally in line with one another,but spaced apart to define a longitudinal channel therebetween having apredetermined width. The rail body is formed from a sheet of material bya process of roll forming.

The present invention disclosed and claimed herein comprises, in anotheraspect thereof, a step rail assembly for a vehicle. The assemblyincludes an elongated rail body having two opposing edges defining alongitudinal channel. At least one mounting bracket is provided having afirst and a second end connected by a bracket arm. The first end isadapted for a rigid connection to a mounting point of the vehicle. Thesecond end has a generally upwardly-facing, generally flat mountingsurface defining a first fastening hole and a first portion of analignment device. A pinch clamp is provided having a major dimension anda minor dimension disposed on generally perpendicular axes. The pinchclamp defines a second fastening hole and a second portion of thealignment mechanism. The major dimension is greater than a width of thelongitudinal channel, and the minor dimension is less than the width ofthe longitudinal channel. The second portion of the alignment device isadapted to selectively engage the first portion and thereby preventrelative rotation between the mounting bracket and the pinch clamp whenthe minor dimension of the pinch clamp is substantially aligned with thelongitudinal channel. The rail body can be rigidly connected to themounting bracket by first loosely inserting a fastener through therespective fastening holes in the mounting surface and the pinch clampto rotatably attach the pinch clamp to the mounting bracket, thenturning the pinch clamp to align the major axis with the longitudinalchannel, then lowering the rail body toward the mounting bracket suchthat the pinch clamp passes between the opposing edges of the rail bodyand the opposing edges come into contact with the mounting surface, thenrotating the pinch clamp to align the major axis perpendicular to thelongitudinal channel such that the clamp overlies the opposing edges ofthe rail body and the first portion of the alignment device engages thesecond portion, and then tightening the fastener to pull the pinch clampand flat face portion of the bracket arm tightly against opposite sidesof the opposing edges of the rail body.

The present invention disclosed and claimed herein comprises, in afurther aspect thereof, a method of forming a step rail of predeterminedlength for a vehicle. A quantity of flat-rolled metal is provided havingan overall length and a substantially finished surface on at least oneside. The substantially finished surface has a layer of protectiveplastic film adhering thereto. The flat-rolled metal is prepared forroll forming while retaining the layer of protective plastic in place onthe substantially finished surface. The flat-rolled metal is roll formedinto a rail body of essentially constant cross section by feeding themetal between successive pairs of rolls that increasingly shape it untilthe desired cross section is completed. The cross section of the railbody has a non-linear, open contour in which the two ends of the shapeare not brought together and the rail body has the substantiallyfinished surface facing outward. The roll formed rail body is thentrimmed to the predetermined length and the layer of protective plasticfilm is removed from the substantially finished surface.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and theadvantages thereof, reference is now made to the following descriptiontaken in conjunction with the accompanying Drawings in which:

FIG. 1 is a perspective view of a step rail in accordance with oneembodiment of the invention, mounted on a SUV (shown in phantom);

FIG. 2 is an enlarged perspective view of the step rail of FIG. 1 andportions of the bracket system;

FIG. 3 is a cross-sectional view of the step rail taken along line 3-3of FIG. 2;

FIG. 4A is an exploded perspective view of the unassembled step rail andbracket system in accordance with another embodiment;

FIG. 4B is a perspective view of the assembled step rail and bracketsystem of FIG. 4 a;

FIG. 5 is a perspective view of the pinch clamp of the step rail andbracket system;

FIG. 6 is a side elevation view of the bracket arm of the step rail andbracket system;

FIG. 7 is a is a perspective view of a side step rail for a vehicleshowing another embodiment of the invention;

FIG. 8 is cross-sectional view thereof taken along line 8-8 of FIG. 7;

FIG. 9 is cross-sectional view thereof taken along line 9-9 of FIG. 7;

FIG. 10 is a front elevation view thereof;

FIG. 11 is a right end view thereof;

FIG. 12 is a left end view thereof;

FIG. 13 is a rear elevation view thereof;

FIG. 14 is a top plan view thereof;

FIG. 15 is a bottom plan view thereof;

FIG. 16 is a perspective view of a side step rail for a vehicle showinganother embodiment of the invention, the cross-sectional, elevation andplan views thereof being substantially similar to those of FIG. 7;

FIG. 17 is a perspective view of a side step rail for a vehicle showingyet another embodiment, the cross-sectional, elevation and plan viewsthereof being substantially similar to those of FIG. 7;

FIG. 18 is a perspective view of a step rail for a vehicle showing asstill further embodiment;

FIG. 19 is a front elevation view thereof;

FIG. 20 is a right end view thereof;

FIG. 21 is a left end view thereof;

FIG. 22 is a rear elevation view thereof;

FIG. 23 is a top plan view thereof;

FIG. 24 is a bottom plan view thereof;

FIG. 25 is an enlarged cross-sectional view thereof taken along line25-25 of FIG. 18, and further is an enlarged cross-sectional view of theembodiment of FIG. 26 taken along line 25-25 of FIG. 26;

FIG. 26 is a perspective view of a step rail for a vehicle showinganother embodiment;

FIG. 27 is a front elevation view thereof;

FIG. 28 is a right end view thereof;

FIG. 29 is a left end view thereof;

FIG. 30 is a rear elevation view thereof;

FIG. 31 is a top plan view thereof;

FIG. 32 is a bottom plan view thereof;

FIG. 33 is a series of sequential end views during the roll formingoperation showing successive profiles of the rail body from view A(first profile) to view Q (final profile);

FIG. 34 is an overlaid series of sequential end views of the rollforming operation of FIG. 33 showing the successive profiles of the railbody from view A (first profile) to view Q (final profile) as viewedfrom a fixed perspective;

FIG. 35 is a cross-sectional side view of the rail body showing minimumsurface finish requirement regions in accordance with anotherembodiment; and

FIG. 36 is a block diagram showing a method of assembling a step rail toa mounting bracket system in accordance with yet another embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, wherein like reference numbers are usedherein to designate like elements throughout the various views,embodiments of the present invention are illustrated and described, andother possible embodiments of the present invention are described. Thefigures are not necessarily drawn to scale, and in some instances thedrawings have been exaggerated and/or simplified in places forillustrative purposes only. One of ordinary skill in the art willappreciate the many possible applications and variations of the presentinvention based on the following examples of possible embodiments of thepresent invention.

Referring now to FIG. 1, there is illustrated one embodiment of a rollformed step rail for a vehicle in accordance with the current invention.The step rail 100 includes a rail body 102 and end caps 104. A bracketsystem 106 is used to attach the step rail 100 to the side of thevehicle 110 (shown in phantom). The bracket system 106 is normally notvisible from a perspective view such as shown in FIG. 1 but has beenshown here for purposes of illustration. The specific location andappearance of the bracket system 106 relative to the rail body 102 isshown in greater detail herein. Additionally, while not shown in theembodiment of FIG. 1, step pads may also be attached to an upper surfaceof the step rail 100 as further described herein.

Referring now to FIG. 2, there is illustrated an enlarged view of thestep rail 100. The mounting brackets 106 include a bracket arm 112having an upper bracket plate 114 adapted for attachment to a vehiclebody. As stated with respect to FIG. 1, the bracket system 106 is notnormally visible from a perspective view, but has been shown as visiblein FIG. 2 for purposes of illustration. In this embodiment, the upperbracket plate 114, includes an upper portion 116, having a plurality ofmounting holes 118 and a lower portion 120 that is angled with respectto the upper portion 116. The lower portion 120 may be angled to providea proper fit to a vehicle frame or sub-frame, to provide additionalclearance for the rail body 102 or a user of the system, or foraesthetic reasons.

Referring now to FIG. 3, there is illustrated a cross sectional view ofthe rail body 102 taken through line 3-3 of FIG. 2. The rail body 102has a relatively thin rail wall 302 that has been formed, preferably byroll forming, into a specialized curve profile as shown. The profileincludes relatively flat top portion 304 disposed between asemi-circular front curved portion 306 and a quarter-circular rearcurved portion 308. A rear mounting lip 310 extends forward from therear curved portion 308. A front mounting lip 312, extends upward andthen rearwards from the front curved portion 306. The respective freeends 314 and 316 of the rear and front mounting lips 310 and 312 aregenerally in line with one another, but spaced apart to define alongitudinal mounting passage 318 having a predetermined width, denotedW_(c).

The rail body 102 is preferably formed of stainless steel material butmay be formed of other steel alloys and/or aluminum alloys. The outersurfaces of the rail body 102 are preferably polished or finished tohave a specific surface finish as further described herein. The railbody 104 profile is a preferably formed by the process of roll forming.It will be appreciated that roll forming involves passing flat rolledmetal sheet stock through successive pairs of rolls that increasinglyshape the originally flat stock into a desired cross section as shown.In a preferred embodiment of the invention, the flat rolled stock has asurface that is pre-finished and is rolled in such a manner that theoriginal surface finish is not damaged by the rolling operation. Thus,after roll forming, the rail body 102 will require little, if any,additional surface finishing to achieve the final desired finish. In amore preferred embodiment, the original flat rolled metal stock has alayer of protective plastic film in place on the substantially finishedsurface. This protective plastic film remains in place during the rollforming operation. After the rail body 102 profile has been fullyformed, the protective plastic may be removed. This protective plasticfilm helps maintain the substantially finished surface of the originalstock in good condition during roll forming.

It will be appreciated that the flat rolled metal stock used for theroll forming operation may start out as coiled metal rolls or as flatsheets. Whether coiled rolls or flat sheets, the flat stock will be fedthrough the roll forming operation in a continuous manner and the railbodies 102 may be trimmed to their final shape after the rolled formcontour has been produced. After trimming to final shape, the end caps104 and step pads (if used) may be added to the rail body. The end caps104 and/or step pads will typically be formed of molded plastic, rubber,or resin, however they may be made of die-cast metal or other materialsin some embodiments.

Referring now to FIGS. 4A and 4B, there is illustrated enlarged views ofthe rail mounting bracket system in accordance with further embodimentsof the invention. As seen in FIG. 4A, the mounting bracket systemincludes the rail body 102, bracket 106, and a pinch clamp 402. Thebracket 106 includes an arm 112 having an upper plate 114 at the upperend and a lower plate 404 at the lower end as previously described. Thelower plate 404 has a body 405 defining a fastener hole 406 and a firstpart 408 of an alignment device. In this case, the first part 408 of thealignment device comprises a pair of holes 410 formed in the body 405.The pinch clamp 402 has a body 412 having a major dimension with arelatively large width, denoted W_(L), and a minor dimension with arelatively short width, denoted W_(s), that is shorter than W_(L). Inthe embodiment shown, the pinch clamp body 412 has a generallyrectangular shape, but this is not required. Rather, it is only requiredthat the pinch clamp body have a major and minor dimension which aredifferent from one another. The pinch clamp 402 further includes afastener hole 414 and a second part 416 of the alignment devicepreviously mentioned (i.e., the one having a first part 408 on the lowerbracket plate body 405). In the embodiment shown, the second part 416 ofthe alignment device comprises a pair of tabs 418 extending downwardfrom the lower face of the pinch clamp body 412.

The mounting bracket system of the current invention allows for a methodof convenient installation of the rail body 102 to the vehicle. Themounting bracket 106 is first mounted to the vehicle using the topmounting bracket 114. The top mounting bracket 114 may be configured tocooperate with pre-existing hold in the frame or sub-frame of avehicles. In some instances it may be necessary that hole be drilledinto the frame or sub-frame in the desired location to accommodate themounting bracket 114. When the bracket 114 is mounted, a fastener, suchas a nut and bolt combination 420 and 422 may be inserted through thefastening holes 414 and 406 and loosely attached to one another torotatably attach the pinch clamp 402 to the mounting bracket 106. Thepinch clamp 402 may then be turned relative to the mounting bracket topplate 404 until the major dimension with length W_(L) is aligned withthe longitudinal channel 318 between the ends 314 and 316 of the railbody 102. Because the fastener 420, 422 is only loosely fastened, thepinch clamp 402 can be lifted slightly from the surface of plate 404 tokeep the first and second portions of the alignment device (in thiscase, tabs 418 and holes 410) from engaging.

The major dimension of the pinch clamp 402 with length W_(L) is selectedto be larger than the width W_(c) of the rail body channel 318, and theminor dimension with length W_(s) is selected to be smaller than thewidth W_(c). The major dimension and minor dimension are generallyperpendicular to one another. Thus, when the major dimension havinglength W_(L) is aligned with the longitudinal channel 318, the minordimension having length W_(s) will be able to pass through thelongitudinal channel 318 which has a width W_(c). In a preferredembodiment, the tabs 418 on the pinch clamp 402 are spaced a part by awidth, denoted W_(t), only slightly larger than the width, denotedW_(b), of the lower plate body 405. This will cause the pinch clamp 402to remain aligned with the major dimension having length W_(L) alignedwith the channel 318 without being held in this position. The rail 102may then be lowered over the pinch clamp until the front and rear lips310 and 312 of the rail rest upon the top of the body 405. The pinchclamp 402 can then be raised slightly to disengage the tabs 418 from thesides of the body 405 and rotated 90 degrees until the major dimensionW_(L) is generally perpendicular to the channel 318. The two portions ofthe alignment device may then engage (i.e., tabs 418 will fall intoholes 410, maintaining the pinch clamp in position). Since the majordimension has a length W_(L) that is larger than the width of channelW_(c), the ends of the pinch clamp will overlie the front and rear lips310 and 312 of the rail body 102. Tightening the fastener 420, 422 atthis point will draw the pinch clamp 402 against the lower plate 404 ofthe bracket 106, securely capturing the rail body 102 and affixing it tothe vehicle. It will be appreciated that since the rail body 102 has agenerally uniform cross section along it's length, the rail body may bemoved longitudinally back and forth for alignment purposes simply byloosening the fastener 420, 422. It will not be necessary to completelyremove the pinch clamp, rather just loosen it slightly so that thepressure between the pinch clamp 402 and the mounting bracket 106 isreduced somewhat.

Referring now also to FIG. 36, there is illustrated a block diagramshowing a method for mounting a step rail and bracket system to avehicle in accordance with another embodiment. Beginning at step 3610,the mounting bracket 106 is mounted to a vehicle. At step 3620, afastener, such as a nut and bolt combination 420 and 422 may be insertedthrough the fastening holes 414 and 406 and loosely attached to oneanother to rotatably attach the pinch clamp 402 to the mounting bracket106. At step 3630, the pinch clamp 402 may then be turned relative tothe mounting bracket top plate 404 until the major dimension with lengthW_(L) is aligned along the length of the vehicle (i.e., along the lengthof the channel in the rail body when installed). At step 3640 the railbody 102 may be placed on the lower plate 404 of the bracket 106 suchthat the major dimension of the pinch clamp 402 with length W_(L) iswithin the longitudinal channel 318 between the ends 314 and 316 of therail body 102. Because the fastener 420, 422 is only loosely fastened,the pinch clamp 402 can be lifted slightly at step 3650 from the surfaceof plate 404 to keep the first and second portions of the alignmentdevice (in this case, tabs 418 and holes 410) from engaging. At step3660 the pinch clamp may be rotated approximately 90 degrees and loweredsuch that the first and second parts of the alignment device areengaged. At step 3670 the fore and aft position of the body rail 102 maybe adjusted relative to the vehicle, and at step 3680 the fastener maybe tightened.

Referring now again to FIG. 4B, there is shown the mounting bracketsystem after the pinch clamp 402 has been fully tightened, capturing therail body 102 between the pinch clamp and the lower plate 404 of thebracket 106. It will be understood that while FIG. 4B illustrates thepinch clamp 402 positioned near the end of the rail body 102, in factthe bracket 106 and clamp 402 may be attached at any point along therail body 102 since the width of the channel W_(c) is substantiallyuniform along the length of the rail body. It will further beappreciated that since the pinch clamp 402 rotates to pass through thechannel in the rail body, it is not required that the ends of the railbody 102 be opened during installation. Therefore, the end caps 104 maybe installed on the rail body without interfering in any way with theinstallation of the rail body 102 on the vehicle.

Referring now to FIG. 5, there is illustrated an additional view of thepinch clamp 402. It will be appreciated that the pinch clamp 402 isshown in an inverted position with respect to that shown in FIG. 4A. Inthis embodiment, the pinch clamp 402 is rectangular having majordimension W_(L) and minor dimension W_(s). It will further beappreciated that in this embodiment the pinch clamp 402 has a U-shapedcross section comprising a relatively flat center portion 422 and siderails 424 and 426. This is a simple and strong configuration, however itis not the only configuration that will work. As previously indicated,other configurations having a major and minor dimensions as previouslydescribed may be used. The pinch clamp 402 may be pressed, cast,machined, or molded, and may be formed from steel, aluminum, alloys, oranother material. In the embodiment of FIG. 5, the first portion 416 ofthe alignment device comprises tabs 418 separated by the distance W_(t).As stated, in a preferred embodiment, the width W_(t) is slightly largerthan the width, denoted W_(b) of the lower plate body 405. The tabs 418may be pressed, punched, machined, or molded into the relatively flatcenter portion 422. The tabs 418 represent only an exemplary second part416 of the alignment device as other devices or methods may be employed.The fastener hole 414 may also be pressed, punched, machined, or moldedinto the flat center portion 422. In the embodiment shown, the fastenerhole 414 is square and designed to cooperate with the bolt 420 (of FIG.4A), which may have a square neck so as to be self anchoring withrespect to the pinch clamp 402.

Referring now to FIG. 6, there is illustrated a side view of themounting bracket 106 to further illustrate various aspects of theinvention. The bracket 106 attaches vertically on the upper plate 114 toa vehicle frame, sub-frame, or other suitable mounting point. Holes 118may be provided at such locations in the upper plate 114 as to matchexisting holes on the vehicle frame or sub-frame to which the bracket106 will be mounted to allow the passage of bolts or other fasteners. Alower portion 120 of the upper plate 114 may also be angled to match thevehicle frame or sub-frame and may also be provided with holes formounting the bracket 106. In some embodiments the lower portion 120 maybe angled to provide additional clearance or for aesthetic reasons.Other embodiments may not provide the lower portion 120.

The bracket 106 also provides a lower plate 404 with a relatively flatbody 405 which may be oriented in a generally horizontal position by thebracket arm 112. The lower plate body 405 provides the first portion ofthe alignment device, which, in this embodiment, comprises holes 410.The holes 410 may be the width W_(t) apart and positioned to match thetabs 422 of FIG. 5. Thus, the pinch clamp 402 may be held in positionrelative to the lower plate 404 by the use of a single fastener (such asthe t422 and bolt 420 of FIGS. 4A-4B) tightly fitted into holes 414 and406. Additionally, as previously described, the pinch clamp may be onlyloosely fastened to the lower plate body 405 and may thus remainrotatable when lifted from the lower plate 404. The bracket 106 may beformed from steel, aluminum, alloys thereof, or other materials. Thebracket 106 and its associated components and dimensions and may formedby machining, casting, molding, pressing, drilling, punching, and/orcombinations of these and other methods.

Referring now to FIGS. 7 through 15, there is illustrated a roll formedstep rail in accordance with another embodiment of the invention. Theroll formed step rail 800 is substantially identical in most respects tothat previously described, including a rail body 802 and end caps 804.In this embodiment, however, step pads 807 and 808 have been added onthe upper flat surface of the rail body 802. In the preferredembodiment, the step pads 807 and 808 are mounted after the rail body802 has been roll formed. The step pads 807 and 808 may be attached withadhesives, fastening studs, or other fastening means to the step rail802. The step pads 807 and 808 may be made from rubber, plastic,polymers, steel, alloys or other materials. The step pads 807 and 808may be formed by molding, casting, or other methods. In a preferredembodiment, the step pads 807 and 808 may be formed of a slip resistantmaterial and may be textured so as to increase the slippage resistance.

The end caps 804 may be made from rubber, plastic, polymers, steel,alloys or other materials. The end caps may be formed by molding,casting, or other methods. In the preferred embodiment, the end caps 804are mounted after the rail body 802 has been formed. The end caps 804may be attached securely with adhesives, fastening studs or other means.As previously described, the end caps may be installed on the rail body802 prior to the rail body being attached to the vehicle due to thedesign of the mounting bracket system 106 and associated components.

FIGS. 10-15 provide various views of the completed step rail. FIG. 10 isa side view illustrating the completed step rail 802 with step pads 807and 808 and end caps 804. FIGS. 11 and 12 illustrate additionalembodiments of the end caps 804 featuring non-slip texturing. FIG. 13illustrates another side view of the step rail 802 from the back side ofthe step rail 802 (i.e., the side that faces the vehicle followinginstallation). FIGS. 14 and 15 represent top and bottom view of thefinished rail body 802, respectively.

Referring now to FIGS. 16 and 17, additional embodiments of the steprail in accordance with the invention are shown. FIG. 16 shows that thestep rail 1600 may have a rail body 1602 of any length, and that twostep pads 1607 and 1608 of any size may be used. FIG. 17 shows that steprail 1700 in accordance with other embodiments may have a rail body 1702of any length and a single step pad 1707 of any length. Each of the steprails 1600 and 1700 may be equipped with end caps 1604 and 1704 similarto those previously described.

Referring now to FIGS. 18-24, a roll formed step rail 1800 in accordancewith additional embodiments of the invention is shown. FIG. 18illustrates a step rail 1800 that is provided without end caps or steppads. The step rail 1800 may be installed and used without end caps orstep rails or may serve as an installation base to which items such asend caps and step rails may be added. FIG. 19 illustrates a side viewshown from the viewpoint of one facing the installed rail 1800. FIGS. 20and 21 illustrate the respective end views of the rail 1800. FIG. 22illustrates the back side of the step rail 1800 (i.e., the side thatfaces the vehicle following installation). FIGS. 23 and 24 illustratetop and bottom views, respectively.

Referring now to FIGS. 25-32, further embodiments of the invention areshown. The step rail 2600 of FIGS. 25-32 is substantially similar to thestep rail 18 of FIGS. 18-24. From FIGS. 25-32 it can be seen that thelength of the step rail 2600 may be chosen according to the applicationand needs of the user or vehicle. FIG. 26 illustrates the installed steprail 2600 while FIG. 25 shows a cross section taken along the line 25 ofFIG. 26. FIG. 25 illustrates the cross section of step rails 1800 and2600. FIG. 27 is a frontal view of the step rail 2600, which may be ofany length and FIGS. 28 and 29 provide the respective end views of thestep rail 2600. FIG. 30 illustrates the back side of the step rail 2600(i.e., the side that faces the vehicle following installation). FIGS. 31and 32 illustrate top and bottom views, respectively.

Referring now to FIGS. 33 and 34, a roll forming operation for producingthe step rail body is described in accordance with yet anotherembodiment of the invention. FIG. 33 is a sequence of end views of railprofiles produced during the roll forming operation, showing thesuccessive profiles of the rail body, from step A (original profile) tostep Q (completed profile). FIG. 34 is an alternative view of theprofiles, showing the successive profiles of the rail body from step Ato step Q from a fixed perspective.

Referring specifically now to FIG. 33, there is illustrated a sequenceof end views (denoted A-Q) of the step rail body showing the sequentialdeformation of the original sheet during the roll forming process. Inview A, the step rail body has the shape of a flat rolled sheet 3300with a top surface 3303, bottom surface 3305 and free ends 3314 and3316. Preferably, the flat rolled sheet 3300 is formed of an austeniticstainless steel, more preferably a 304 stainless steel having a nominalcomposition of 18% chromium and 8% nickel. The flat rolled sheet 3300has a thickness (denoted T_(s)) which is preferably within the rangefrom 15 gauge to 17 gauge (standard steel thickness) and more preferably16 gauge. Stated another way, T_(s) is preferably within the range fromabout 0.0673 inches to about 0.0538 inches, and more preferably in therange from 0.058 inches to about 0.065 inches.

The top surface 3303 of the sheet 3300 is preferably pre-finished to itsfinal appearance before roll forming. In preferred embodiments theoriginal (i.e., pre-roll formed) top surface 3303 has a brushed finishwith a typical surface roughness of Ra 40 micro-inches or less, and morepreferably has a No. 4 Finish (ASTM) having a typical surface roughnessof Ra 25 micro-inches or less.

Further, in preferred embodiments, the original top surface 3303 of thesheet 3300 is covered by a protective film 3307, which protects thesurface finish during roll forming. In more preferred embodiments, theprotective film 3307 is a PVC (polyvinyl chloride) film secured to thetop surface 3303 with a medium tack adhesive that allows the film toremain attached during roll forming, but can be removed manuallythereafter. The protective film 3307 is preferably transparent so thatthe film and top surface 3303 can be visually inspected for the presenceof undesirable debris or contamination before roll forming.

Referring still to FIG. 33, the originally flat sheet 3300 as previouslydescribed in View A is passed through a series of roll-forming stages asillustrated in Views B-Q. As is known in the roll-forming industry, eachstage of the roll forming line has bending rolls that make a step-wisechange to some portion of the cross sectional profile of the sheet 3300,such that the sheet is gradually transformed from the original flatprofile shown in View A to the fully formed profile shown in View Q. Thechanges between adjacent stages are small enough such that the sheet3300 may be passed continually along the roll forming line withoutstopping between the original profile (View A) and the completed profile(View Q).

In a preferred embodiment, the initial bending stages (shown by ViewsB-E) sequentially deform the sheet 3300 beginning at the free ends 3314and 3316 and forming substantially complete front and rear mounting lips3312 and 3310 while the center section 3311 remains substantiallyunchanged (i.e.; flat). Next, the intermediate bending stages (shown byViews F-M) sequentially deform the outer ends of the center section 3311to substantially form the quarter circular rear curved portion 3308 andsimultaneously partially form the semi-circular front curved portion3306. It will be appreciated that during the intermediate bending stages(Views F-M), the mounting lips 3310 and 3312 are not further deformed;rather their orientation simply changes as they “ride” on the respectivecurved portions 3308 and 3306, which are being deformed. Next, the finalbending stages (shown by Views N-Q) sequentially deform the front curvedportion 3306 to its completed step rail configuration as shown in ViewQ. This final configuration is substantially similar to that previouslydescribed herein, e.g., in connection with FIG. 3, and includes allfeatures of the step rail body including the channel 3318 of widthW_(c).

Referring now to FIG. 34, there is illustrated an alternative sequenceof end views (similarly denoted Views A-Q) of the rolled sheet 3300 asit is transformed from its original flat rolled configuration (View A)into the completed step rail profile (View Q). The views shown in FIG.34 are substantially identical to those shown in FIG. 33, with the viewsdenoted using the same letter in the two figures corresponding to oneanother. In FIG. 34, however, the various views are depicted as if thecenter portion 3311 of the sheet 3300 was fixed in place. This providesa different perspective to allow further appreciation of the successivebending stages in the roll forming process.

After the sheet 3300 has passed through all stages (Views A-Q) of theroll forming operation, the formed sheet will have a substantiallyconstant cross section of the desired step rail profile as previouslydescribed herein, e.g., in connection with FIG. 3. The formed sheet maythen be cut to any desired length to form a step rail body. Anyprotective plastic film may then be removed from the outer surface ofthe body. Also, step pads and/or end caps may be added to the step railbody as previously described herein, e.g., in connection with FIGS.7-17. The step rail may be mounted to a vehicle using a bracketingsystem as previously described herein, e.g., in connection with FIGS.4A, 4B, 5, 6 and 36.

After roll forming, it is preferred, although not required, that theouter surface of the completed step rail exhibit a minimum surfacefinish that varies according to a position along the periphery of therail body profile. This surface finish is preferably obtained withoutadditional post-roll forming operations. FIG. 35 illustrates such aminimum surface finish requirement diagram.

Referring now to FIG. 35, there is shown a cross-sectional view of astep rail body after roll forming to form a profile substantiallysimilar to that previously described. The step rail body 3500 has arelatively thin rail wall 3502, a relatively flat top portion 3504disposed between a semi-circular front curved portion 3506 and aquarter-circular rear curved portion 3508. A rear mounting lip 3510extends forward from the rear curved portion 3508 and a front mountinglip 3512 extends upwards and then rearwards from the curved frontportion 3506. The respective free ends 3514 and 3516 of the front andrear mounting lips are generally in line with one another, but spacedapart as in previously described herein to define a longitudinalmounting passage 3518 having a predetermined width. It is understood,when mounted on the vehicle, the step rail will have the large curved(front) side 3506 facing the street and the small curved (rear) side3508 facing the vehicle. In this embodiment, the roll forming processprovides that, following the removal of any protective plastic film fromthe outer surface of the rail, the rail's outer surface will haveparticular minimum surface finish characteristics as follows. A firstperipheral segment (denoted A in FIG. 35) subtends approximately 160°angle from the upper rear of curve 3508 to the lower front of curve 3506as shown. Segment A is the most critical to the appearance of the steprail. Segment A must be substantially blemish-free after roll forming. Asecond peripheral segment (denoted B) subtends approximately 45° anglefrom the lower front of curve 3506 to the edge of the front mounting lip3512 as shown. Segment B is considered to have secondary importance tothe appearance of the step rail. Segment B may have only minor toinsignificant blemishes after roll forming. A third peripheral segment(denoted C) subtends approximately 45° angle from the upper rear to thelower rear as shown. It has tertiary importance to the appearance of therail. In segment C, visual blemishes are allowed within a reasonabledegree. Finally, a fourth peripheral segment (denoted D) subtendsapproximately 110° angle from the front mounting lip 3512 to the rearmounting lip 3510 (including the inner surfaces visible through thechannel). Segment D is not considered important to the appearance of therail. In segment D, visual blemishes which do not alter the productdimensions are allowable. Using the roll forming process of the currentinvention allows such minimum surface finish requirements to be achievedwithout requiring post roll-forming polishing operations. This hassignificant advantages in reducing production costs.

It will be appreciated by those skilled in the art having the benefit ofthis disclosure that this invention provides a roll formed step rail fora vehicle, a mounting bracket system, and process and methods relatingto the fabrication and/or use of same. It should be understood that thedrawings and detailed description herein are to be regarded in anillustrative rather than a restrictive manner, and are not intended tolimit the invention to the particular forms and examples disclosed. Onthe contrary, the invention includes any further modifications, changes,rearrangements, substitutions, alternatives, design choices, andembodiments apparent to those of ordinary skill in the art, withoutdeparting from the spirit and scope of this invention, as defined by thefollowing claims. Thus, it is intended that the following claims beinterpreted to embrace all such further modifications, changes,rearrangements, substitutions, alternatives, design choices, andembodiments.

1. A step rail assembly for a vehicle, comprising: an elongated railbody having two opposing edges defining a longitudinal channel; at leastone mounting bracket having a first and a second end connected by abracket arm, the first end adapted for a rigid connection to a mountingpoint of the vehicle, the second end having a generally upwardly-facing,generally flat mounting surface defining a first fastening hole and afirst portion of an alignment device; a pinch clamp having a majordimension and a minor dimension disposed on generally perpendicularaxes, the pinch clamp defining a second fastening hole and a secondportion of the alignment mechanism, the major dimension being greaterthan a width of the longitudinal channel, the minor dimension being lessthan the width of the longitudinal channel; wherein the second portionof the alignment device is adapted to selectively engage the firstportion and thereby prevent relative rotation between the mountingbracket and the pinch clamp when the minor dimension of the pinch clampis substantially aligned with the longitudinal channel; wherein the railbody can be rigidly connected to the mounting bracket by first looselyinserting a fastener through the respective fastening holes in themounting surface and the pinch clamp to rotatably attach the pinch clampto the mounting bracket, then turning the pinch clamp to align the majoraxis with the longitudinal channel, then lowering the rail body towardthe mounting bracket such that the pinch clamp passes between theopposing edges of the rail body and the opposing edges come into contactwith the mounting surface, then rotating the pinch clamp to align themajor axis perpendicular to the longitudinal channel such that the clampoverlies the opposing edges of the rail body and the first portion ofthe alignment device engages the second portion, and then tightening thefastener to pull the pinch clamp and flat face portion of the bracketarm tightly against opposite sides of the opposing edges of the railbody.
 2. The assembly of claim 1, wherein the first portion of thealignment device comprises a plurality of tabs protruding downward fromthe pinch clamp, and the second portion of the alignment devicecomprises a plurality of holes defined by the mounting surface, each ofthe plurality of holes being configured to receive one of the pluralityof tabs.
 3. The assembly of claim 2, wherein the mounting surface has awidth in a direction aligned with the longitudinal channel that is lessthan a distance between a first tab and a second tab of the plurality oftabs protruding from the pinch clamp.
 4. The assembly of claim 1,wherein the first portion of the alignment device comprises a pluralityof holes defined in the pinch clamp, and the second portion of thealignment device comprises a plurality of tabs, each of the plurality ofholes being configured to receive one of the plurality of tabs.
 5. Theassembly of claim 1, wherein the fastener cooperates with the secondfastening hole to be self anchoring with respect to the pinch clamp. 6.The assembly of claim 1, wherein the elongated rail body substantiallyconceals the second end of the mounting bracket and the mounting surfacewhen viewed from a direction in the same plane as the opposing edges. 7.The assembly of claim 1, further comprising first and second rail capsattached over first and second ends of the elongated rail body.
 8. Theassembly of claim 1, further comprising a step pad attached to theoutward side of a flat surface defined by the elongated rail body on aside opposite the longitudinal channel.
 9. The assembly of claim 1,wherein the second portion of the alignment device selectively engagesthe generally flat mounting surface of the bracket when the majordimension is aligned with the longitudinal channel thereby preventingrotation between the bracket and pinch clamp.
 10. The assembly of claim9, wherein the second portion of the alignment device comprises tabsprojecting downwardly from the pinch clamp and spaced apart a dimensionW_(t), and the generally flat mounting surface of the bracket has awidth parallel to the longitudinal channel that is less than W_(t),whereby the tabs engage the edges of the generally flat mounting surfaceto prevent relative rotation therebetween when the major dimension isaligned with the longitudinal channel.